The Interdisciplinary Liver Research Program is providing the framework and support for all liver-related research projects in the Schools of Medicine and Pharmacy. It is based on the combined facilities and resources of the School of Medicine, the School of Pharmacy, the Moffitt-University Hospital, the San Francisco General Hospital, and the San Francisco Veterans Administration Hospital. The goal of the Program is to consolidate and expand on-going liver-related research projects; to foster interdisciplinary communication and cooperation between investigators of different departments and schools; to support and expand existing or planned collaborative projects; to provide resources, expertise and skills in areas which presently are not represented but which conceptually are related to major on-going projects. The main emphasis of the Program is on hepatic physiology and pathophysiology, particularly as they relate to the reactions of the liver to injury. The proposed research projects are grouped in the following categories: a) hepatitis and cirrhosis; b) hepatic drug metabolism and disposition; c) hepatocyte function and structure; d) hepatic secretion, cholestasis, and bile acids; e) development and differentiation of the liver, and f) bile pigment and porphytin metabolism.